Patterns on tropical marine mollusc shell mirror gene expression patterns

Nov 22, 2006
Patterns on tropical marine mollusc shell mirror gene expression patterns
Picture of a juvenile H. asinina shell. Credit: Daniel Jackson

Scientists have identified a group of genes that control the formation of shapes and colour patterns on the shell of the tropical marine mollusc referred to as ‘abalone’. A study published today in the open access journal BMC Biology reveals that the shape and colour patterns on the shell of the mollusc mirror the localised expression of specific genes in the mantle, a layer of skin situated just below the shell. The authors of the study identify one gene in particular that controls the formation of blue dots on the shell of the mollusc.

Daniel Jackson, Bernard Degnan and colleagues from the University of Queensland, Australia, collaborated with colleagues from the Department of Geobiology at the University of Göttingen, Germany to analyse gene expression in the tropical abalone Haliotis asinina. They sequenced 530 randomly-selected genes expressed in the mantle tissue of the young abalone.

Jackson et al. identified 331 genes that encode proteins expressed in the mantle. Using a bioinformatics approach they find that 26% (85) of these genes encode secreted proteins. Jackson et al. then analysed the expression patterns of 22 of the genes encoding secreted proteins. They find that each gene is expressed in a specific, discrete area of the mantle, involved in the formation of a specific layer, shape or colouration pattern of the shell.

They identify one gene in particular, Has-sometsuke, whose expression pattern maps precisely to pigmentation patterns in the shell. Blue dots on the shell of the abalone correspond to zones of high Has-sometsuke expression. By comparing the abalone DNA sequences with the genome of another related mollusc, Lottia scutum, the authors also show that genes encoding the secreted mantle proteins, which they call the ‘secretome’, in abalone, are likely to be rapidly evolving genes.

Jackson et al. conclude: “The unexpected complexity and evolvability of this secretome and the modular design of the molluscan mantle enables the diversification of shell strength and design, and as such must contribute to the variety of adaptive architectures and colours found in mollusc shells.”

Source: BioMed Central

Explore further: How an ancient vertebrate uses familiar tools to build a strange-looking head

add to favorites email to friend print save as pdf

Related Stories

X-ray imaging reveals a complex core

Jul 04, 2014

Macromolecular complexes composed of self-assembling proteins and nucleic acids hold promise for a wide range of applications, including drug delivery, sensing and molecular electronics. Scientists have developed ...

Advancing medicine, layer by layer

Jul 02, 2014

Personalized cancer treatments and better bone implants could grow from techniques demonstrated by graduate students Stephen W. Morton and Nisarg J. Shah, who are both working in chemical engineering professor ...

Toward fixing damaged hearts through tissue engineering

Jan 22, 2014

In the U.S., someone suffers a heart attack every 34 seconds—their heart is starved of oxygen and suffers irreparable damage. Engineering new heart tissue in the laboratory that could eventually be implanted into patients ...

Recommended for you

Final pieces to the circadian clock puzzle found

7 hours ago

Researchers at the UNC School of Medicine have discovered how two genes – Period and Cryptochrome – keep the circadian clocks in all human cells in time and in proper rhythm with the 24-hour day, as well ...

Measuring modified protein structures

11 hours ago

Swiss researchers have developed a new approach to measure proteins with structures that change. This could enable new diagnostic tools for the early recognition of neurodegenerative diseases to be developed.

New insights in survival strategies of bacteria

11 hours ago

Bacteria are particularly ingenious when it comes to survival strategies. They often create a biofilm to protect themselves from a hostile environment, for example during treatment with antibiotics. A biofilm is a bacterial ...

Bangladesh meet begins to save endangered tigers

12 hours ago

Some 140 tiger experts and government officials from 20 countries met in the Bangladeshi capital Dhaka on Sunday to review progress towards an ambitious goal of doubling their number in the wild by 2022.

Study solves the bluetongue disease 'overwintering' mystery

Sep 12, 2014

The bluetongue virus, which causes a serious disease that costs the cattle and sheep industries in the United States an estimated $125 million annually, manages to survive the winter by reproducing in the insect that transmits ...

User comments : 0